Holding the GIL for too long could disrupt the heartbeat due to non-copying sends.

The following cell repeatedly calls a function that holds the GIL for five seconds.

The heartbeat will fail after a few iterations prior to fixing Issue #1260.


In [1]:
import sys
import time

from cython import inline

def gilsleep(t):
    """gil-holding sleep with cython.inline"""
    code = '\n'.join([
        'from posix cimport unistd',
        'unistd.sleep(t)',
    ])
    while True:
        inline(code, quiet=True, t=t)
        print time.time()
        sys.stdout.flush() # this is important

gilsleep(5)

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